Wooden Paving Tile

ABSTRACT

A paving system that uses a number of individual pavers with defined void spaces between the pavers. Each paver is made entirely out of natural wood, such as Black Locust wood. A matrix, such as a wire mesh, may be used to maintain the void spaces before and during installation. The void spaces may be filled with gravel or another permeable material. The pavers may have the form of tiles, such as cubic tiles, and may be positioned in some cases with their grain oriented vertically.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is concerned with wooden pavers and tiles adapted to complete the construction, decoration and/or landscaping of outdoor areas.

2. Description of Related Art

Concrete and asphalt are ubiquitous in urban environments, yet these paving methods, while durable and easy to create, are impermeable and prevent water from reaching underground aquifers. Precipitation that lands on an impermeable surface will either become standing water and evaporate, or will run down slope, potentially coming into contact with any number of contaminants until it reaches an area where groundwater can permeate the surface. In regions with high levels of precipitation, impermeable surfaces greatly contribute to flooding, which often results in costly infrastructural damage. By contrast, in regions with little precipitation, preventing water from infiltrating into the substrate, and in certain cases, underground aquifers, can have numerous negative structural and environmental impacts.

Another unfortunate side effect of impermeable paving methods, such as concrete and asphalt, is that they absorb heat as short-wave radiation during the day and release that stored thermal energy as long-wave radiation at night, contributing to what is known as an “urban heat-island” effect. The “urban heat-island” effect refers to the significant heating of an urban area due to human activities, largely as a result of reduced vegetation and the widespread use of impermeable paving methods. To compensate for the heat, people use more energy to run fans and air conditioners, creating a vicious cycle of more pollution, more greenhouse gas effect, and even higher temperatures. Apart from these environmental consequences, asphalt and concrete aren't aesthetically unique or visually pleasing.

Wood is an age-old material, and has been used for paving. Although wood tends not to contribute to the urban heat island effect and has more aesthetically pleasing characteristics, wood blocks and tiles aren't very durable or rot resistant and will tend to disintegrate when left in contact with the ground for long periods of time. For that reason, wood is traditionally treated with creosote, tar, or other chemicals, as shown by Ruff, U.S. Pat. No. 853,034, a 1907 patent. While wood treatments have advanced over the last century, treating wood blocks to improve their durability and environmental resistance is complex and involves environmental risks.

SUMMARY OF THE INVENTION

One aspect of the invention relates to a paver. The paver is made entirely of natural wood, such as Black Locust wood, and may be in the form of a block or tile. A plurality of wooden pavers set in the earth with a regular defined distance between each creates a paved area, such as a patio, while allowing water to permeate the surface and potentially reducing unwanted solar heating. A wire mesh, or another form of matrix, may be used in some embodiments in order to maintain the correct spacing during installation.

In one embodiment according to this aspect of the invention, each paver may have the general shape of a cube. In other words, each paver may have four sidewalls connected at the corners by one superior and one inferior face of identical dimension. Depending on the installation, aesthetics, and other factors, the grain of each paver may be oriented vertically. Alternatively, some pavers may have their grain oriented in other directions.

These and other aspects, features, and advantages of the invention will be set forth in the description that follows.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The invention will be described with respect to the following drawing figures, in which like numerals represent like features throughout the invention, and in which:

FIG. 1 is a perspective view of a plurality of wooden paving tiles installed to form a patio according to one embodiment of the invention;

FIG. 2 is a top plan view of the wooden paving tiles of FIG. 1 before installation, showing a wire mesh upon which the wooden tiles are arranged;

FIG. 3 is a sectional elevational view of the wooden paving tiles of FIG. 1 after installation in a landscape; and

FIG. 4 is an isometric sectional view of the plurality of wooden paving tiles of FIG. 1 installed in the landscape.

DETAILED DESCRIPTION

FIG. 1 is a perspective view of a patio, generally indicated at 10, according to one embodiment of the invention. The patio 10 is comprised of a plurality of wooden pavers 12 constructed entirely of untreated natural wood. In the illustrated embodiment, the pavers 12 have the form of tiles.

As was described above, soft woods are not typically suitable for paving without first undergoing some form of chemical treatment. The same is true of many common hardwoods. There are a number of exotic hardwoods that may be durable enough to be suitable for paving tiles 12, but many of those woods have a high oil content, and thus tend to be slippery when wet. High oil content can also prevent tropical hardwoods from accepting decorative colorants, such as stain. Additionally, non-sustainable harvesting methods and international trade restrictions make exotic hardwoods expensive and difficult to acquire.

In the illustrated embodiment of the patio 10, the wooden tiles 12 are made of untreated Black Locust wood (Robinia pseudoacacia). Black Locust wood is a domestically grown and sustainably harvested lumber well suited for the embodiments of the invention. Among the favorable properties of Black Locust wood are a Janka Hardness rating of 1,700 lbf, durability, and organic rot resistance. While the present inventor does not wish to be bound by any particular theory, the pores of Black Locust wood are typically filled with minerals instead of oil, which allows the wood to be especially durable and resistant to slip hazards while retaining some capacity to accept decorative stain. Given the favorable properties of Black Locust wood, it is believed that without any chemical treatment, the plurality of paving tiles 12 may last up to sixty years. Moreover, at the end of their useful life, the paving tiles 12 can be incinerated without significantly polluting the environment. Although the present inventor has found Black Locust wood to be appropriate for embodiments of the invention, woods having other properties that compare favorably with those of Black Locust wood could be used.

FIG. 2 is a top plan view of the wooden tiles 12 before installation of the patio 10 of FIG. 1. In the illustration of FIG. 2, all of the wooden tiles 12 are shown as having their grain 14 oriented vertically. Wooden tiles arranged so that their grain is vertical, i.e., with the end grain 14 facing up, may exhibit greater strength and durability. This may be particularly helpful if the patio 10 or other paved area is likely to be subjected to large loads. However, the grain 14 need not always be oriented vertically.

The present inventor has found it advantageous to use a cube-shaped hard wood tile 12, as that allows the installer to choose the most aesthetically presentable face of the tile 12 and position it accordingly during installation without changing the way that the tiles 12 fit together. This means that the grain 14 of each tile 12 may be oriented differently; however, the visible surface of the patio 10 will be more aesthetically pleasing as a whole. Of course, depending on the application, the tiles 12 could be rectangular, cylindrical, or a variety of shapes. In some cases, the individual tiles 12 could be different shapes, for example, shapes that are intended to be complementary to one another.

In order to create the patio 10 of FIG. 1, The plurality of wooden tiles 12 could be placed directly in or on the ground; however, the present inventor has found that laying wooden tiles 12 on top of a matrix, such as a wire mesh 16, can be advantageous for keeping the tiles 12 appropriately placed during installation. After installation, the wire mesh 16 provides space to allow water to permeate the finished installation. In many cases, the paving tiles 12 need not be fastened to the wire mesh 16, although in some embodiments, wooden tiles 12 could be fastened to the mesh 16 with any type of fastener, such as a nail or staple. When a matrix, such as wire mesh 16, is used, the tiles 12 may be prepared and sold in 3×3, 3×4, 6×6, or 9×9 blocks of tiles 12, as shown in FIG. 2.

The wire mesh 16 could have a variety of mesh or hole sizes depending on the application. In a fastened embodiment of the invention, the wire mesh 16 could be constructed of a metal such as iron or mild steel, such that it oxidizes upon coming into contact with earth and water, and disintegrates over some period of time.

The permeability of the overall patio 10 or paved surface is derived from void spaces, generally indicated at 18, which allow groundwater to infiltrate beneath the ground surface. The void space 18 could be ⅜″ in one embodiment of the invention, but the spacing is not critical so long as it allows water to permeate and is not so large that it creates an uneven surface. However, regulatory requirements in effect in particular locales may specify minimum or maximum spacings (e.g., ½ inch space) between pavers in order to maintain an even, easily navigable surface for wheelchair users. The void space could be filled with any number of materials to maintain the space 18.

FIG. 3 is a sectional elevational view of the installed patio 10 from FIG. 1 showing paving tiles 12 placed above the wire mesh 16. The void space 18 of this embodiment is filled with a permeable material, such as crushed stone 20 (e.g. ASTM #8), so as to help maintain an appropriate void space 18 and allow water to pass between paving tiles 12.

As shown in FIG. 3, there may be any number of underlayers beneath the wire mesh 16, or, if no wire mesh 16 is used, beneath the tiles 12 themselves. A number of methods for underlying paving tiles 12 are known to those with skill in the art, and any such methods may be used. In particular, additional layers of material with equal or greater permeability compared to the crushed stone 20 would be appropriate. In FIG. 3, there are three layers 20, 22, 24, each with material of a defined and graduated size. As one example, the layers 22, 24 may be crushed rock 22 (e.g. ASTM #57) and gravel 24 (e.g. ASTM #2) so as to promote water passage underground.

FIG. 4 is a partially sectional perspective view of one embodiment of the installed patio 10 from FIG. 1, showing the tiles 12 relative to the wire mesh 16 and the underlying layers 20, 22, 24. Each paving tile 12 is uniformly separated from the next by void space 18 that is maintained by filling with crushed stone 20 (e.g. ASTM #8). In FIGS. 3 and 4, the wire mesh 16 is shown as being a flat sheet below the tiles 12. However, in some embodiments, the wire mesh 16 could be shaped with raised portions that extend between tiles 12.

As shown in FIGS. 3 and 4, the tiles 12 are dimensioned and arranged such that the patio 10 itself presents a level top surface. As with the spacing between tiles 12, local and regional laws or regulations may specify a maximum unevenness, or deviation in height, from one tile 12 to the next. For example, at the time of writing, the Americans With Disabilities Act (ADA), which is the basic controlling law in the United States, requires a vertical change in level of no more than ¼ inch (6.4 mm). While it may not be necessary to comply with such laws and regulations in all embodiments or installations, it is often preferable if the tiles 12 are sized, dimensioned, and positioned to comply with local laws and regulations. Of course, one advantage of the tiles 12 is that if any particular tiles 12 cause a height or evenness problem, individual tiles 12 can be sanded or planed to bring the surface as a whole into compliance.

The plurality of wooden tiles 12 is not expected to absorb short-wave radiation during the day and thus, should not release long-wave radiation during the night, which could help to reduce the aforementioned effects of an urban heat island. Additionally, the aesthetic qualities are considerably more unique and potentially pleasing than methods of paving that involve concrete.

While the invention has been described with respect to certain exemplary embodiments, the embodiments are intended to be illuminating rather than limiting. Modifications and changes may be made within the scope of the invention, which is defined by the appended claims. 

1. A paving system, comprising: a plurality of untreated Black Locust wood pavers arranged in a defined pattern relative to one another, the defined pattern creating regular void spaces therebetween; wherein the void spaces and the paving system as a whole are water permeable in a finished installation.
 2. The paving system of claim 1, further comprising a matrix that maintains the defined pattern and the void spaces.
 3. The paving system of claim 2, wherein the matrix comprises a wire mesh.
 4. The paving system of claim 3, wherein the wood pavers are disposed in or on the wire mesh.
 5. The paving system of claim 4, wherein the wood pavers are attached to the wire mesh.
 6. The paving system of claim 1, wherein the wood pavers are arranged with their grain oriented vertically.
 7. The paving system of claim 1, wherein the wood pavers are cubic.
 8. The paving system of claim 1, further comprising a matrix, wherein the plurality of pavers are arranged in a rectangular array on or in the matrix.
 9. A paving system, comprising: a plurality of untreated Black Locust wood pavers arranged in a defined pattern relative to one another on a matrix, the defined pattern creating regular void spaces therebetween, the void spaces being maintained with a permeable medium, such that the paving system as a whole is water permeable.
 10. The paving system of claim 9, wherein the permeable medium is gravel.
 11. The paving system of claim 10, wherein the permeable medium comprises a plurality of layers of gravel.
 12. The paving system of claim 11, wherein the permeable medium comprises a plurality of layers of gravel of different sizes, arranged in graduated sizes of gravel, with small gravel maintaining the void spaces and larger layers of gravel underneath.
 13. The paving system of claim 10, further comprising one or more layers of gravel or rock beneath the wood pavers, the one or more layers of gravel or rock being progressively coarser than the gravel of the permeable medium.
 14. The paving system of claim 13, wherein the matrix comprises a wire mesh.
 15. A paving system, comprising: a backing matrix; a plurality of untreated Black Locust wood pavers arranged in a defined pattern relative to one another on the backing matrix, the defined pattern creating regular void spaces therebetween; a permeable medium disposed between the wood pavers and filling the void spaces; and one or more layers of underlayment beneath the matrix, the one or more layers of underlayment having graduated sizes or porosities.
 16. The paving system of claim 15, wherein the backing matrix comprises a wire mesh.
 17. The paving system of claim 15, wherein the wood pavers are fastened to the backing matrix.
 18. The paving system of claim 15, wherein the wood pavers are substantially cubic tiles.
 19. The paving system of claim 15, wherein the permeable medium comprises gravel.
 20. The paving system of claim 19, wherein the one or more layers of underlayment comprise gravel or crushed rock. 